<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Vue Event</title>
  <script src="https://cdn.bootcss.com/vue/2.6.10/vue.js"></script>
  <style>
    .grandpa {
      width: 800px;
      height: 500px;
      border: 1px solid gray;
    }

    .daddy {
      width: 700px;
      height: 450px;
      border: 1px solid brown;
    }

    .sonny {
      width: 500px;
      height: 200px;
      border: 1px solid gold;
    }
  </style>
</head>

<body>
  <div id="app">
    <div class="grandpa">


    </div>
  </div>
  <script>
    // [疑惑]
    // 1. 绑定的事件，和组件的层级有没有关系？可以从下到上，子组件向父组件触发吗？
    // 2. 事件通信是否为一对一的？可以多监听和触发吗？
    // 3. Vue通信方式总结：组件链事件调用、emit&on事件总栈、Vuex全局状态
    // [参考]
    // https://cn.vuejs.org/v2/guide/migration.html#%E4%BA%8B%E4%BB%B6
    

    var vm = new Vue({
      el: '#app',
      methods: {

      }
    })
  </script>
</body>

</html>